The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 01, 1984
Filed:
Oct. 21, 1982
Romano G Pappalardo, Sudbury, MA (US);
Thomas E Peters, Chelmsford, MA (US);
GTE Laboratories Incorporated, Waltham, MA (US);
Abstract
Phosphors and a method for producing yellow-emitting tin-manganese coactivated calcium fluorophosphate phosphors having improved brightness comprises the steps of blending a powder mixture including the phosphates, carbonates, fluorides and oxides of calcium, tin, and manganese together with an ammonium salt, and firing the mixture at a temperature of between about 1100.degree. C. and about 1300.degree. C. for a period sufficient to produce a luminescent composition. The presence of an ammonium compound in the initial powder blend promotes the proper atmosphere during the firing step to insure the incorporation of proper levels of tin and manganese ions in the final phosphor.